1. Field of the Invention
This invention pertains generally to retrieval of roadway hazard warning markers, and more particularly to an apparatus for the automatic retrieval of safety cones from the roadway.
2. Description of the Background Art
Many highway construction, maintenance and repair activities require physical separation between a designated work area and lanes that remain open to traffic. Busy highways, fast moving traffic and debris traveling at high speeds create an extremely hazardous environment that presents a danger to work crews. High visibility safety markers are commonly used to close a number of lanes and create a safety zone where crew workers can perform maintenance, repair, and construction on the highway. Although a variety of safety markers exist, traffic cones are the most common because they can be stored compactly, are easily transported, and require no assembly. In addition, traffic cones are widely available in different sizes and weights to satisfy various traffic and road conditions.
Manual deployment of traffic cones is a method used worldwide, although several automated cone placement and retrieval devices have been developed to assist with this tedious procedure.
One such device is capable of retrieving and storing approximately between 1500 and 2000 traffic cones, and can be operated by a single driver up to speeds above 35 mph. This device picks up standing cones by first capturing them with two revolving paddle wheels. The traffic cones are then moved upward and rearward by a conveyor. The cone is then placed in a depositing area where cones are stacked vertically. Once the cones are stacked to a predetermined height, the cone stack is released on sloped rollers and placed on the rear end of the vehicle. The cone stacks could also be moved laterally on rollers to maximize the vehicle's storage capacity.
The problem that is apparent with this device is its impracticality due to the bulky nature of the retrieving mechanisms and the large frame of the vehicle. In addition, cones that are knocked over present a difficult problem for this machine since it has no means of manipulating the cones on the road surface.
Another known device provides for the automated retrieval of traffic cones has an operating speed of approximately 11 mph and a storage capacity of 240 traffic cones. During retrieval procedures, the driver must manipulate the cone into one of two positions using short vertical bars that can orient the cones in either a base first or a cone tip first configuration. If manipulated into a base first configuration, the cone can be picked up as if it were an upright cone. However, if the cone is placed in a cone tip first position, a horizontal bar is lowered to contact the base of the cone and flip it so that the cone falls into the base first configuration. With the vehicle moving forward, a prong enters through the open bottom of the cone and lifts the cone upwards. Once a cone has been picked up, a chain link conveyor is used to lift the cone upwards to a chute that leads to the storage area. The cone is stripped from the prong by a simple bar mechanism and it falls through the chute. The falling cone is stacked vertically in one of ten vertical cylinders that form a circular ring.
The problem presented by this device is it can only retrieve custom sized cones and not a wide variety of cone designs. In addition, the large size of the device makes it difficult to adapt to various truck frames. Furthermore, the device cannot be used to retrieve cones in a reverse direction which is generally the preferred direction for retrieval.
A third such known device that collects cones consists of a rotating wheel mechanism operating off of the bed of a truck. The rotating wheel mechanism includes two conical disks that are spaced to wedge a traffic cone between them and is deployed to the side of a truck for retrieval of cones. For retrieval, the cones are simply run over by the rotating wheel. The cone becomes wedged between the two disks and is carried upwards as the large wheel rotates. Another bar is used to free the cone from the wheel and to allow the operator to manually store the cone.
This device exhibits difficulties under certain situations. For example, a significant amount of road space is required for the rotating wheel to deploy and retract. It is also necessary for deployment and retraction to be performed at the work site because when the wheel is deployed, the truck becomes too cumbersome to maneuver in traffic. The deployment and retraction of the wheel also requires manual assistance from personnel located on the road. This exposure to traffic is extremely hazardous to the crew, and since the operator of the device must remain seated within the truck bed, there exists a high risk due to the moving traffic, the potentially hazardous mechanisms of the rotating wheel and loose debris on the road. Also, the operator who performs the tasks within the truck bed is subject to lifting and repetitive motion-type injuries.
Thus, there is a need for an automated traffic cone retriever that is capable of retrieving cones when the cones are in any position on the roadway, that is space efficient and adaptable to a variety of trucks, and that eliminates the need of a worker within the bed area of the truck. The present invention satisfies these needs, as well as others, and generally overcomes the deficiencies found in the background art.